Method of producing seams.



H. J. DAHL. METHOD 0I' PRODUGING SBAMS. APPLICATION FILED APR. 1s, 1914.

Llg Patented Mar. 2, 1915.

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HARRY J'. DAI-IL, 0F NYACK, NEW YORK, ASSIG-NOR T0 LUCIUS N. LITTAUEB, OF GLOVERSVILLE, NEVJ YORK.

METHOD OF PRODUGING SEAMS.

Specification of Letters Patent.

Patented Mar. 2, 1915.

Application filed Apri113, 1914. Serial No. 831,403.

To all 'whom t may concern Be it known vthat I, HARRY J. DA1-IL, a citizen of the United States, residing at Nyack, in the county of Rockland and State of New York, have invented certain new and useful Improvements in Methods of Producing Scams, of which the following is a specification. y

The present invention has to do with an improved method of forming flat seams on knit and other fabrics adapted for use in the making of garments, it more particularly having to do with a method of producing flat covered seams, the object of the invention being to provide an improved fiat seam and an improved method of forming the same whereby such seams can be produced by onesimple operation on a sewing machine and whereby the necessity of utilizing different machines and different operations for producing such a fiat seam is avoided.

A sewing machine adapted to carry out this method will form the subject-matter of a separate application, and therefore only so much thereof as is necessary to illustrate the several steps of the method is shown in the drawings.

1n the drawings accompanying and forming part of this specification, Figure 1 is a side elevation of the elements of the sewing machine used in producing the fiat seam; Fig. 2 is a left-hand end view looking in the direction of the arrow in Fig. 1 with the work removed; Fig. 3 are views of the element or device for turning the edges of the work inside out and looking from the rear of Fig. l; Fig. 4 is a perspective. View of the elements shown in Fig. 1 with the trimming knives removed and illustrating the manner in which the several layers of work are carried past the sewing machine; Fig. 5 is a detail view of the trimmer knives; Fig. 6 illustrates a piece of work showing the needle thread forming a covered flat seam; Fig. 7 illustrates the same with the looper thread cooperating with the needle thread; and Fig. 8 is a view of the lsame illustrating how the edges of the two plies of the material are brought together and secured by the stitches.

The lower trimmer blade or knife 5 is provided with a cutting edge 8, see Fig. 5, for the bottom ply of work, and an upper cutting edge 9 for the top ply of work, while the other trimmer blade or knife 6 has a cutting edge 10 coperating with the edge 8 of the knife 5 for the bottom ply of work, and avcutting edge 11 cooperating with the edge 9 of the knife 5 for the top ply of work. The feed dog 12 operates through the throat plate 4 to traverse the bottom ply of work, while the top feed 13 traverses the top ply of work at a uniform speed with the bottom ply. A supplemental throat plate 14 coperates with the feed dog 12 to feed the bottom ply, while the feed dog 13 coperates with the top of this supplemental throat plate to feed the'top ply of work.

A presser foot 15 having an automatic lift, at which time the work is moved by the feeds, is supported by a shank 16 and is provided with an upturned end or toe 17, vand a short tongue over which the stitches may be formed. This presser foot is slotted as at 18, see Figs. 2 and 4, to receive the extended portion of the feed dog 13, which feed dog is carried on a pin 21 of the arm 20, it being so hung as to move on the pin, the arm 20, by suitable mechanism, giving the usual four motions to this feed dog 13. A reciprocating plunger 22 having a roundedend 24 and carrying a blade 23, see Figs. 3 and 4, and mounted in a suitable bearing 25 so as to properly aline and have the same vertical movements as the supplemental throat plate 14, is located in position so that the blade 23 will the proper time and force such edges inthe lower part of said wardly into the recess 26 of the supplemental throat plate, 14, see Fig. 3, and thus turn the edges inside out; in other words shift or bend such edges from the position 27, see upper portion of Fig. 3, to the position 28, see lower portion of Fig. 3.

In making this improved seam, the top ply of fabric A and the bottom ply of fabric B is started in the machine as at 30.-31,:"Fig-. 1f, As the machine is started the bottom feed 12 comes into position to grip and feed the lower ply B, while the feed 13 also comes into position upon the supplemental throat plate 14 so as to feed the upper ply A, the two plies thus being fed separate from each other and spaced apart as it were, and at each cycle of the machine the work is advanced to a point where it meets the trimming` knives which are placed one above the other to properly trim the plies A and B of the work thereby toprepare the edges thereof to receive the stitches.

Any of the well known covering seams which can be produced by the common overstitch method is suitable to carry out this method so far as the stitch-forming instrumentalities are concerned, and therefore a detailed description of the stitching mechanismv is deemed unnecessary.

As the plies A and B of the work reach their stitching position the needle penetrates these plies A and B, passing itsthread 4through the material, and thus makes the stitches C represented by Fig. 6. vThe looper or spreader, thread is carried over 'if' lthe usual tongue of the throat plate and the supplemental tongue 32 shown in dotted lines, Fig.4, and which supplemental tongue v32 assists in the stitch formation and prevents the threads from drawing into the work, so that the edges of the work will not project between them. As the stitch is formed the looper thread is carried around the edge of the work to' the top edge of one of the plies where it is `ioined with the spreader thread D. Each time the needle is inthe work the plunger 22 is reciprocated y in its bearing 25 by suitable means provided for that purpose, so that the blade 23 thereof will strike the seam at 27, see upper part of Fig. 3,. and force it into the recess 26 of the supplemental throat plate 14 as shown by Fig. 3. As the needle rises and the feeds come in position to again advance the work, the plunger is shifted away from the seam and the supplemental throat plate thereby to permit the plies A and B of the work to freely pass through the machine. As the feeding takes place the seam opens in such manner that the edges abut as illustrated in Fig. 8, so that as the vwork is delivered from the machine the two plies A 'and B of the work readily lie fiat,

see Figs. 6 and 7 and with the edges abutting one another.

It is to be understood that the supplemental throat plate 14 acting upon the bottom ply B has a rising and falling motion caused by the action of the feed dog underneath it, while the top feed 13 has the usual four motions upon the supplemental throat plate, and that the automatic presser foot has' a lifting motion to and from the work so as to grip the work while the needle penetrates the same and releases the work when the feed is acting upon such work, it being understood, of course, that the presser foot and supplemental throat plate and the upper feed are such that when the usual presser bar is raised all this mechanism, being operatively connected thereto, will also be raised to permit the work to be placed into position or removed.

From the foregoing it will be observed that the several plies of material are fed to the stitching mechanism spaced apart, one above the other, and that they have the edges, while in such position, trimmed, and then such trimmed edges are stitched, and during this stitching operation the stitched edges are turned inside so that the edges will abut against each other and the two plies will open fiat, and that the several steps of this method are carried out during the feeding of the work to and from the stitching mechanism and as the stitching takes place.

I claim as my invention:

1. The method of forming a flat seam which consists in stitching several plies of work together and during such stitching operation turning the stitched edges of the work between the plies. v

2. rEhe method of forming a iat covered sea-m which consists in stitching several plies of work together to cover the edges thereof and during such stitching operation turning the stitched edges of the work between the plies and then opening the work up fiat so that the edges will abut.

3. The method of forming a fiat seam which consists in feeding several plies of work spaced apart one above the other, stitching the edges, and then, during the stitching operation, turning the stitched edges of the work between the plies.

4. The method of forming a flat seam which consists in feeding several plies of work together, one above the other, stitching the edges then during the stitching operation turning the stitched edges of the work between the plies and then opening the work up fiat so that the edges will abut.

5. The method of forming a flat seam which consists in stitching several plies of work together, and then exerting pressure on the stitched edges in a direction transverse to the line of stitches thereby to turn direction transverse to the line of stitches the stitched edges of the Work between the thereby to turn such stitched edges between plies. the plies and then opening the Work up flat 6. The method of forming a flat covered so that the edges will abut. 5y seam which consists in feeding several plies Signed at Nyack, in the county of Rock- 15 of Work spaced apart one above the other, land, this 10th day of April, 1914.

trimming the edges thereof, stitching the HARRY J. DAI-IL. r, trimmed edges of the several plies together Vitnesses: *l to form a covered seam, then exerting lat- OLoF. S. PETERSON,

10 eral pressure on such stitched edges in a JOHN W. KANE.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

